#include <iostream>
#include <map>
#include <cmath>
#include <vector>
#include <algorithm>
using namespace std;

const long long Target = 500000000000000000LL;
long long N;
long long A[59], C[59];
long long B[59], D[59];

int main() {
	// Step 1. 入力
	cin >> N;
	for (int i = 1; i <= N; i++) cin >> A[i] >> B[i];
	for (int i = 1; i <= N; i++) C[i] = A[i];
	for (int i = 1; i <= N; i++) D[i] = B[i];

	// Step 2. 3 手読み
	long long MinV = (1LL << 60);
	vector<pair<int, int>> Answer;
	for (int i = 2; i <= N; i++) {
		for (int j = i + 1; j <= N; j++) {
			for (int k = 2; k <= N; k++) {
				for (int l = k + 1; l <= N; l++) {
					// Cand は最後の 1 手で操作するカードの候補
					vector<int> Cand = { i,j,k,l };
					for (int m : Cand) {
						for (int n = 1; n <= N; n++) C[n] = A[n];
						for (int n = 1; n <= N; n++) D[n] = B[n];

						// シミュレーション (1 手目)
						long long avgC1 = (C[i] + C[j]) / 2LL;
						long long avgD1 = (D[i] + D[j]) / 2LL;
						C[i] = avgC1; D[i] = avgD1;
						C[j] = avgC1; D[j] = avgD1;

						// シミュレーション (2 手目)
						long long avgC2 = (C[k] + C[l]) / 2LL;
						long long avgD2 = (D[k] + D[l]) / 2LL;
						C[k] = avgC2; D[k] = avgD2;
						C[l] = avgC2; D[l] = avgD2;

						// シミュレーション (3 手目)
						long long avgC3 = (C[m] + C[1]) / 2LL;
						long long avgD3 = (D[m] + D[1]) / 2LL;
						C[m] = avgC3; D[m] = avgD3;
						C[1] = avgC3; D[1] = avgD3;

						// 誤差の計算
						long long err = max(abs(C[1] - Target), abs(D[1] - Target));
						if (MinV > err) {
							MinV = err;
							Answer.clear();
							Answer.push_back(make_pair(i, j));
							Answer.push_back(make_pair(k, l));
							Answer.push_back(make_pair(m, 1));
						}
					}
				}
			}
		}
	}

	// Step 3. 出力
	cout << Answer.size() << endl;
	for (int i = 0; i < Answer.size(); i++) cout << Answer[i].first << " " << Answer[i].second << endl;
	return 0;
}